1. Technical field
The invention lies in the field of strength training (of a human body) by subjecting muscles, joints, and 1e skeleton to resistance due to gravity caused by weights. More specifically, the training concerns abdominal training with the exercise forms of situps or crunch, and back training with the exercise form of back extensions (also called hyper extensions). The invention is a compact equipment of the type free weight (in contrast to machine).
2. Definitions
The following definitions are provided for reference. Crunch is an exercise performed by using the abdominal muscles to curl up and pull the chest region towards the hips. Essentially only the abdominal muscles are being used, and the hips and thighs should not move during the exercise. The exercise is normally performed from a starting position lying with the back against the floor (or other horizontal support) with thighs in 90 degrees relative to the support and with the lower legs loosely resting (not locked) on a bench or similar. When doing situps not only are the abdominal muscles volitionally used, but also the hip flexors and the frontal thigh muscles.
Situps are done from a starting position lying on the back with the shoulders level with, or lower than, the hips. The legs are bent and usually with the lower legs or the feet locked under some restraint. The exercise is then performed by lifting as well as curling the upper body towards the knees. Both crunch and situps may be performed with twisted upper body, and then not only the straight muscle of the belly (rectus abdominis) but also to a great extent the waist muscles (obliques), are being used. Back extension is an exercise that is performed using a roman chair in which the person can lock his or her legs in a horizontal position, with the belly and the face facing the floor. The exercise is performed by bending the upper body at the hips, thereby lowering the head and the shoulders until the upper body hangs relaxed approximately vertically. And thereafter the upper body is raised, and the spine is extended with a curling movement, whereby the person returns to horizontal position. The lower back (erector spinae) predominantly used in the exercise, but also to some extent the muscles between the shoulder blades, the buttocks, and the back thighs.